Technical requirements for connecting photovoltaic power station to power system
1 Scope
This document specifies the technical requirements for connecting photovoltaic (PV) power station to power system in terms of active power, reactive voltage, fault ride through, operational adaptability, power prediction, power quality, simulation models and parameters, and secondary systems, as well as their testing and evaluation contents.
This document is applicable to the construction, production and operation of newly built, renovated and expanded PV power stations connected to the grid through voltage class above 10 kV. This document may also serve as a reference for PV power stations equipped with energy storage device.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 12325 Power quality - Deviation of supply voltage
GB/T 12326 Power quality - Voltage fluctuation and flicker
GB/T 14285 Technical code for relaying protection and security automatic equipment
GB/T 14549 Quality of electric energy supply - Harmonics in public supply network
GB/T 15543 Power quality - Three-phase voltage unbalance
GB/T 19862 General requirements for monitoring equipment of power quality
GB/T 22239 Information security technology - Baseline for classified protection of cybersecurity
GB/T 24337 Power quality - Interharmonics in public supply network
GB/T 29321 Technical specification for reactive power compensation of PV power station
GB/T 31464 The grid operation code
GB/T 32900 Technical specification for relaying protection of photovoltaic power station
GB/T 33982 Technical specification for grid connection protection of distributed resources
GB/T 36572 Guidelines of cyber security protection for electric power system supervision and control
GB/T 37408 Technical requirements for photovoltaic gird-connected inverter
GB/T 37409 Testing specification for photovoltaic grid-connected inverter
GB 38755 Code on security and stability for power system
GB/T 40289 Technical requirement of power control system for photovoltaic power station
GB/T 40581 Calculation specification for power system security and stability
GB/T 40594 Technical guide for power grid and source coordination
GB/T 40595 Guide for technology and test on primary frequency control of grid-connected power resource
GB/T 40604 Information exchange technical requirements for energy dispatch and operation of renewable energy station
GB/T 40607 Technical requirements for dispatching side forecasting system of wind or photovoltaic power
GB/T 50866 Design code for photovoltaic power station connecting to power system
DL/T 448 Technical administrative code of electric energy metering
DL/T 5003 Code for design of dispatch automation in power system
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 40581, GB/T 40594 and GB/T 40595 and the following apply.
3.1
photovoltaic (PV) power station
power generation system that uses the photovoltaic effect of PV cells to directly convert solar radiation energy into electrical energy
Note: It generally includes transformers, inverters and PV arrays, as well as related auxiliary facilities, etc.
3.2
inverter
device that converts direct current into alternating current
3.3
point of connection
high-voltage side busbar or node of the booster station for PV power stations with booster stations; output summary point of the PV power stations for PV power stations without booster stations
3.4
PV power forecasting
establishing a PV power generation prediction model based on historical power, meteorological data, and equipment operation status of the PV power station, and using irradiance, power, or numerical weather forecast data as inputs to the model, combined with the equipment status and operating conditions of the PV power generation system, to predict the active power of the PV power station for a period of time in the future
Note: According to the forecast period, it is divided into medium-term, short-term and ultra-short-term PV power forecasts.
3.5
medium-term PV power forecasting
prediction of the active power of the PV power station from 0:00 the next day to the next 240h, with a time resolution of 15 min
3.6
short-term PV power forecasting
prediction of the active power of the PV power station from 0:00 the next day to the next 72h, with a time resolution of 15 min
3.7
ultra-short-term PV power forecasting
prediction of the active power of the PV power station in the next 15 min to 4h, with a time resolution of 15 min
3.8
low voltage ride through of PV power station
capability of a PV power station to operate continuously without disconnecting from the grid within a certain range and time interval when the voltage of point of connection at the PV power station drops due to power system accidents or disturbances
3.9
high voltage ride through of PV power station
capability of a PV power station to operate continuously without disconnecting from the grid within a certain range and time interval when the voltage of point of connection at the PV power station rises due to power system accidents or disturbances
3.10
low-high voltage ride through of PV power station
capability of a PV power station to operate continuously without disconnecting from the grid within a certain range and time interval of voltage drop and rise when the voltage of point of connection at the PV power station first drops and then rises due to power system accidents or disturbances
Note: Referred to as low-high voltage ride through.
3.11
dynamic reactive current increment of PV power station
amount of change in reactive current injected or absorbed by a PV power station into the power system during low or high voltage ride through relative to the reactive current injected or absorbed into the power system before the voltage drop or rise
Note: Reactive current refers to capacitive reactive current.
3.12
rise time of dynamic reactive current of PV power station
time required from the time when the voltage at the point of connection drops or rises to the trigger setpoint until the dynamic reactive current increment of the PV power station reaches 90% of the incremental target value
3.13
islanding
state in which part of a power grid containing load and power supply continues to operate in isolation after being separated from the main grid
Note: Islanding can be divided into unintentional islanding and intentional islanding. The unintentional islanding refers to the unintentional and uncontrolled occurrence of islanding; the intentional islanding refers to the intentional occurrence of islanding according to the pre-configured control strategy.
3.14
anti-islanding
prevent the occurrence of unintentional islanding
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Active power
5 Reactive voltage
6 Fault ride through
7 Operational adaptability
8 Power forecasting
9 Power quality
10 Simulation models and parameters
11 Secondary system
12 Test and evaluation